The present invention relates to the use of acetyl L-carnitine and its pharmacologically accetable salts for producing a composition suitable for controlling mood disorders in individuals not presenting permanent pathological alterations of the central nervous system (CNS) by restoring the normal balance of neurotransmitter levels.
For the purposes of the present invention what is meant by xe2x80x9cmood disordersxe2x80x9d are those disorders which present as behavioural alterations of a depressive or manic type and, in particular, those disorders that present as oscillations between depressive and manic states alternating in the same individual. According to the present invention, these disorders also include the so-called premenstrual syndrome and states of bulimia.
Normal variations in mood (melancholy, mildly depressed states, anguish or joy and moderate excitement) constitute habitual aspects of daily life and must be distinguished from the pathological fluctuations of affective disorders.
Nevertheless, increasingly wide oscillations in affective attitudes and in that complex series of behavioural reactions and expressions, whether towards the self or towards external reality, which we define synthetically as xe2x80x9cmoodxe2x80x9d, would appear to affect an increasingly large population, consisting mainly of young individuals. Though the extent of such oscillations fails to reach the threshold of pathological relevance, this phenomenon is beginning to have substantial repercussions on important aspects of family life and on social and personal relations with profound consequences even of a socio-economic nature.
The main cause of this phenomenon probably has to do with the profound changes in lifestyle which have occurred, particularly with regard to young individuals, over a relatively short space of time.
Whereas, on the one hand, the opportunities for socialising (from travel and holidays even in far-off locations to attending public events and frequenting public meeting places, such as discotheques, aimed mainly at attracting a youthful population) have increased enormously compared to the past, amongst other things as a by-product of the boom in affluence, this phenomenon also presents worrying negative aspects such as the increased use of beverages with a strong alcohol content and the ever wider diffusion of psycho-active substances and of soft and hard drugs.
Set against the liberalisation of sexual habits and the increasingly widespread use and greater safety of contraceptive methods is the fear of sexually transmitted diseases, the most notable, of course, being AIDS, with its deterrent burden of anxiety which can have adverse repercussions on the normal expression of libido in both male and female subjects.
It is therefore hardly surprising that increasingly large numbers of the younger population are suffering from mood disorders.
These disorders which have a tendency to become chronic, but which exclude the precipitation of major or decidedly bipolar, cyclothymic depression disorders, are currently classified as dysthymias (DSM IV, 300.40) according to the definition provided by the authoritative Diagnostic and Statistical Manual of Mental Disorders (DSM IV) published by the American Psychiatric Association.
In these dysthymic individuals, who present a reduced social functional capability due to the chronic nature of their disorders, and certainly not as a result of the severity of their depressive or manic disturbances, there are often associated disorders of eating habits, with lack of appetite or bulimia, insomnia or hypersomnia, asthenia and fatigue, and reduced self-esteem, concentration and decision-making ability.
The attempts made to date to treat the mood disorders described above with well-known tricyclic antidepressants such as imipramine, nortriptyline, desipramine, amitriptyline etc., have failed to yield satisfactory results, whereas, in younger subjects particularly, their troublesome side effects such as sedation, dry mouth, tremors, postural vertigo, blurred vision, sweating and constipation are poorly tolerated.
It has now been found that acetyl L-carnitine and its pharmacologically acceptable salts constitute an effective means of treating the above-described mood disorders essentially without presenting any of the side effects typical of tricyclic antidepressants.
The object of the present invention thus consists in the use of acetyl L-carnitine or of one of its pharmacologically acceptable salts to produce a composition suitable for controlling mood disorders in individuals not presenting permanent pathological alterations of the central nervous system (CNS) by restoring the normal balance of neurotransmitter levels.
It is important to note that, since the subjects who are to receive the compositions of the present invention are essentially healthy and do not present fluctuations of pathological significance in their affective or mood disorders, the compositions of the invention may present themselves not only as pharmaceutical compositions, but also as health foods, medical foods or nutraceuticals, or as components of such products, containing other active ingredients, dietary supplements, vitamins, co-enzymes, mineral substances and the like in combination with acetyl L-carnitine.
The compositions of the invention are formulated, as regards their presentation form, nature of the unit dose form, weight and so on, in such a way as to favour administration of 500-3000 mg/day of acetyl L-carnitine or a molar equivalent amount of one of its pharmacologically acceptable salts to subjects who need it, either in a single dose or according to a multidose administration regimen.
In cases in which the subject suffering from a mood disorder, as defined in the context of the invention described herein, is also a bulimic or overweight subject (bulimia and depression often being associated manifestations in the same subject), the compositions may also advantageously include an effective amount of 5-hydroxy-tryptophane (5-HTP) in addition to acetyl L-carnitine or one of its pharmacologically acceptable salts.
Compositions suitable for such subjects are those which, as a result of their presentation form, type of unit dose form, weight and so on, favour the administration to the subject of 500-1500 mg/day of acetyl L-carnitine or a molar equivalent amount of one of its pharmacologically acceptable salts and 300-700 mg/day of 5-hydroxy-tryptophane.
The efficacy of acetyl L-carnitine for the treatment of mood disorders according to the invention has been demonstrated, amongst other things, by a clinical trial which will be described here below.